﻿//
// RC4Tests.cs
//
// Author: Jeffrey Stedfast <jestedfa@microsoft.com>
//
// Copyright (c) 2013-2025 .NET Foundation and Contributors
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//

using MailKit.Security.Ntlm;

namespace UnitTests.Security.Ntlm {
	[TestFixture]
	public class RC4Tests
	{
		[Test]
		public void TestArgumentExceptions ()
		{
			using (var rc4 = new RC4 ()) {
				var buffer = new byte[16];

				Assert.That (rc4.InputBlockSize, Is.EqualTo (1), "InputBlockSize");
				Assert.That (rc4.OutputBlockSize, Is.EqualTo (1), "OutputBlockSize");
				Assert.That (rc4.CanReuseTransform, Is.False, "CanReuseTransform");
				Assert.That (rc4.CanTransformMultipleBlocks, Is.True, "CanTransformMultipleBlocks");

				Assert.Throws<InvalidOperationException> (() => { var x = rc4.Key; });
				Assert.Throws<ArgumentNullException> (() => { rc4.Key = null; });
				Assert.Throws<ArgumentException> (() => { rc4.Key = Array.Empty<byte> (); });

				rc4.GenerateIV ();
				rc4.GenerateKey ();
				rc4.CreateDecryptor ();
				rc4.CreateEncryptor ();

				// TransformBlock input buffer parameters
				Assert.Throws<ArgumentNullException> (() => rc4.TransformBlock (null, 0, buffer.Length, buffer, 0));
				Assert.Throws<ArgumentOutOfRangeException> (() => rc4.TransformBlock (buffer, -1, buffer.Length, buffer, 0));
				Assert.Throws<ArgumentOutOfRangeException> (() => rc4.TransformBlock (buffer, 0, -1, buffer, 0));

				// TransformBlock output buffer parameters
				Assert.Throws<ArgumentNullException> (() => rc4.TransformBlock (buffer, 0, buffer.Length, null, 0));
				Assert.Throws<ArgumentOutOfRangeException> (() => rc4.TransformBlock (buffer, 0, buffer.Length, buffer, -1));

				// TransformFinalBlock
				Assert.Throws<ArgumentNullException> (() => rc4.TransformFinalBlock (null, 0, buffer.Length));
				Assert.Throws<ArgumentOutOfRangeException> (() => rc4.TransformFinalBlock (buffer, -1, buffer.Length));
				Assert.Throws<ArgumentOutOfRangeException> (() => rc4.TransformFinalBlock (buffer, 0, -1));
			}
		}

		static void AssertEncrypt (byte[] key, byte[] input, byte[] expected)
		{
			using (var rc4 = new RC4 ()) {
				var output = new byte[input.Length];

				rc4.Key = key;

				rc4.TransformBlock (input, 0, input.Length, output, 0);

				for (int i = 0; i < output.Length; i++)
					Assert.That (output[i], Is.EqualTo (expected[i]), $"output[{i}]");
			}

			using (var rc4 = new RC4 ()) {
				rc4.Key = key;

				var output = rc4.TransformFinalBlock (input, 0, input.Length);

				for (int i = 0; i < output.Length; i++)
					Assert.That (output[i], Is.EqualTo (expected[i]), $"output[{i}]");
			}
		}

		[Test]
		public void TestEncryptExample1 ()
		{
			var expected = new byte[] { 0x74, 0x94, 0xC2, 0xE7, 0x10, 0x4B, 0x08, 0x79 };
			var key = new byte[] { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF };
			var text = new byte[] { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };

			AssertEncrypt (key, text, expected);
		}

		[Test]
		public void TestEncryptExample2 ()
		{
			byte[] expected = new byte[] { 0xF1, 0x38, 0x29, 0xC9, 0xDE };
			byte[] key = new byte[] { 0x61, 0x8A, 0x63, 0xD2, 0xFB };
			byte[] text = new byte[] { 0xDC, 0xEE, 0x4C, 0xF9, 0x2C };

			AssertEncrypt (key, text, expected);
		}

		[Test]
		public void TestEncryptExample3 ()
		{
			byte[] expected = new byte[] {
				0x35, 0x81, 0x86, 0x99, 0x90, 0x01, 0xe6, 0xb5, 0xda, 0xf0, 0x5e, 0xce, 0xeb, 0x7e, 0xee, 0x21,
				0xe0, 0x68, 0x9c, 0x1f, 0x00, 0xee, 0xa8, 0x1f, 0x7d, 0xd2, 0xca, 0xae, 0xe1, 0xd2, 0x76, 0x3e,
				0x68, 0xaf, 0x0e, 0xad, 0x33, 0xd6, 0x6c, 0x26, 0x8b, 0xc9, 0x46, 0xc4, 0x84, 0xfb, 0xe9, 0x4c,
				0x5f, 0x5e, 0x0b, 0x86, 0xa5, 0x92, 0x79, 0xe4, 0xf8, 0x24, 0xe7, 0xa6, 0x40, 0xbd, 0x22, 0x32,
				0x10, 0xb0, 0xa6, 0x11, 0x60, 0xb7, 0xbc, 0xe9, 0x86, 0xea, 0x65, 0x68, 0x80, 0x03, 0x59, 0x6b,
				0x63, 0x0a, 0x6b, 0x90, 0xf8, 0xe0, 0xca, 0xf6, 0x91, 0x2a, 0x98, 0xeb, 0x87, 0x21, 0x76, 0xe8,
				0x3c, 0x20, 0x2c, 0xaa, 0x64, 0x16, 0x6d, 0x2c, 0xce, 0x57, 0xff, 0x1b, 0xca, 0x57, 0xb2, 0x13,
				0xf0, 0xed, 0x1a, 0xa7, 0x2f, 0xb8, 0xea, 0x52, 0xb0, 0xbe, 0x01, 0xcd, 0x1e, 0x41, 0x28, 0x67,
				0x72, 0x0b, 0x32, 0x6e, 0xb3, 0x89, 0xd0, 0x11, 0xbd, 0x70, 0xd8, 0xaf, 0x03, 0x5f, 0xb0, 0xd8,
				0x58, 0x9d, 0xbc, 0xe3, 0xc6, 0x66, 0xf5, 0xea, 0x8d, 0x4c, 0x79, 0x54, 0xc5, 0x0c, 0x3f, 0x34,
				0x0b, 0x04, 0x67, 0xf8, 0x1b, 0x42, 0x59, 0x61, 0xc1, 0x18, 0x43, 0x07, 0x4d, 0xf6, 0x20, 0xf2,
				0x08, 0x40, 0x4b, 0x39, 0x4c, 0xf9, 0xd3, 0x7f, 0xf5, 0x4b, 0x5f, 0x1a, 0xd8, 0xf6, 0xea, 0x7d,
				0xa3, 0xc5, 0x61, 0xdf, 0xa7, 0x28, 0x1f, 0x96, 0x44, 0x63, 0xd2, 0xcc, 0x35, 0xa4, 0xd1, 0xb0,
				0x34, 0x90, 0xde, 0xc5, 0x1b, 0x07, 0x11, 0xfb, 0xd6, 0xf5, 0x5f, 0x79, 0x23, 0x4d, 0x5b, 0x7c,
				0x76, 0x66, 0x22, 0xa6, 0x6d, 0xe9, 0x2b, 0xe9, 0x96, 0x46, 0x1d, 0x5e, 0x4d, 0xc8, 0x78, 0xef,
				0x9b, 0xca, 0x03, 0x05, 0x21, 0xe8, 0x35, 0x1e, 0x4b, 0xae, 0xd2, 0xfd, 0x04, 0xf9, 0x46, 0x73,
				0x68, 0xc4, 0xad, 0x6a, 0xc1, 0x86, 0xd0, 0x82, 0x45, 0xb2, 0x63, 0xa2, 0x66, 0x6d, 0x1f, 0x6c,
				0x54, 0x20, 0xf1, 0x59, 0x9d, 0xfd, 0x9f, 0x43, 0x89, 0x21, 0xc2, 0xf5, 0xa4, 0x63, 0x93, 0x8c,
				0xe0, 0x98, 0x22, 0x65, 0xee, 0xf7, 0x01, 0x79, 0xbc, 0x55, 0x3f, 0x33, 0x9e, 0xb1, 0xa4, 0xc1,
				0xaf, 0x5f, 0x6a, 0x54, 0x7f
			};
			byte[] key = new byte[] {
				0x29, 0x04, 0x19, 0x72, 0xFB, 0x42, 0xBA, 0x5F, 0xC7, 0x12, 0x77, 0x12, 0xF1, 0x38, 0x29, 0xC9
			};
			byte[] text = new byte[] {
				0x52, 0x75, 0x69, 0x73, 0x6c, 0x69, 0x6e, 0x6e, 0x75, 0x6e, 0x20, 0x6c, 0x61, 0x75, 0x6c, 0x75,
				0x20, 0x6b, 0x6f, 0x72, 0x76, 0x69, 0x73, 0x73, 0x73, 0x61, 0x6e, 0x69, 0x2c, 0x20, 0x74, 0xe4,
				0x68, 0x6b, 0xe4, 0x70, 0xe4, 0x69, 0x64, 0x65, 0x6e, 0x20, 0x70, 0xe4, 0xe4, 0x6c, 0x6c, 0xe4,
				0x20, 0x74, 0xe4, 0x79, 0x73, 0x69, 0x6b, 0x75, 0x75, 0x2e, 0x20, 0x4b, 0x65, 0x73, 0xe4, 0x79,
				0xf6, 0x6e, 0x20, 0x6f, 0x6e, 0x20, 0x6f, 0x6e, 0x6e, 0x69, 0x20, 0x6f, 0x6d, 0x61, 0x6e, 0x61,
				0x6e, 0x69, 0x2c, 0x20, 0x6b, 0x61, 0x73, 0x6b, 0x69, 0x73, 0x61, 0x76, 0x75, 0x75, 0x6e, 0x20,
				0x6c, 0x61, 0x61, 0x6b, 0x73, 0x6f, 0x74, 0x20, 0x76, 0x65, 0x72, 0x68, 0x6f, 0x75, 0x75, 0x2e,
				0x20, 0x45, 0x6e, 0x20, 0x6d, 0x61, 0x20, 0x69, 0x6c, 0x6f, 0x69, 0x74, 0x73, 0x65, 0x2c, 0x20,
				0x73, 0x75, 0x72, 0x65, 0x20, 0x68, 0x75, 0x6f, 0x6b, 0x61, 0x61, 0x2c, 0x20, 0x6d, 0x75, 0x74,
				0x74, 0x61, 0x20, 0x6d, 0x65, 0x74, 0x73, 0xe4, 0x6e, 0x20, 0x74, 0x75, 0x6d, 0x6d, 0x75, 0x75,
				0x73, 0x20, 0x6d, 0x75, 0x6c, 0x6c, 0x65, 0x20, 0x74, 0x75, 0x6f, 0x6b, 0x61, 0x61, 0x2e, 0x20,
				0x50, 0x75, 0x75, 0x6e, 0x74, 0x6f, 0x20, 0x70, 0x69, 0x6c, 0x76, 0x65, 0x6e, 0x2c, 0x20, 0x6d,
				0x69, 0x20, 0x68, 0x75, 0x6b, 0x6b, 0x75, 0x75, 0x2c, 0x20, 0x73, 0x69, 0x69, 0x6e, 0x74, 0x6f,
				0x20, 0x76, 0x61, 0x72, 0x61, 0x6e, 0x20, 0x74, 0x75, 0x75, 0x6c, 0x69, 0x73, 0x65, 0x6e, 0x2c,
				0x20, 0x6d, 0x69, 0x20, 0x6e, 0x75, 0x6b, 0x6b, 0x75, 0x75, 0x2e, 0x20, 0x54, 0x75, 0x6f, 0x6b,
				0x73, 0x75, 0x74, 0x20, 0x76, 0x61, 0x6e, 0x61, 0x6d, 0x6f, 0x6e, 0x20, 0x6a, 0x61, 0x20, 0x76,
				0x61, 0x72, 0x6a, 0x6f, 0x74, 0x20, 0x76, 0x65, 0x65, 0x6e, 0x2c, 0x20, 0x6e, 0x69, 0x69, 0x73,
				0x74, 0xe4, 0x20, 0x73, 0x79, 0x64, 0xe4, 0x6d, 0x65, 0x6e, 0x69, 0x20, 0x6c, 0x61, 0x75, 0x6c,
				0x75, 0x6e, 0x20, 0x74, 0x65, 0x65, 0x6e, 0x2e, 0x20, 0x2d, 0x20, 0x45, 0x69, 0x6e, 0x6f, 0x20,
				0x4c, 0x65, 0x69, 0x6e, 0x6f
			};

			AssertEncrypt (key, text, expected);
		}
	}
}
